CORECRAMMING
FAT is the storehouse of energy for us in our body. We are made by nature to store fat in time to need to supply energy to our body, when we don't have quick food or energy source as in starving or dieting.
Fat burning occurs or we use fat continuously to supply energy to our bodily needs example as in talking,siting,walking ,eating etc. So we can say that when we are not exercising the main source of energy for our body is mainly fat. But when we start increasing physical activity the percentage of energy sources shift from fat to muscle glycogen and as we go to intensive exercise most of the energy comes from muscle glycogen , that's why when you do sprints or high intensity weights or exercise you tire easily because as compared to fat aerobic respiration energy source ,muscle glycogen gives energy mostly by anaerobic respiration with lactic acid as byproduct,so that's why you experience that burning pain while doing high repetition or with heavy exercise all because or lactic acid accumulation.
So now the question arises what should be the ideal speed and weight for fat burning and answer is not that simple as everyone is built differently with different bmi and Energy level. Exercise program is maintained according to needs and goal. If the goal is to fat burning then anaerobic workout or mixed workout as combination of cardio and weight training will help the best to achieve fat burning.
For fat burning there are many ways ;-
First with the use of cardiovascular exercise mainly with treadmill and cross-trainer to walk for hours and lose weight which majorly on cost of muscle loss.
Secondly mixed workout with combination of cardio and weight training so that to target weight loss and along with that with weight training develop muscle too so that one can work harder and better so that increase the bmi and lose those extra calories continuously. As with weight training muscle mass increase and with it bmi increases which is the basal meatabolic index of body as this much calories are required everytime for a body to sustain. so thus more bmi means more calories burn and thus more weight loss.
Thirdly with High intensive exercise this is meant for progressive schedule as in this regime all the exercises are done with high power and either high repetition or heavy repetition. it forces the body to use all the calories present and also increases the bmi which again help in calories consumption.
Thus there are many ways to train one person depending upon the goal and time duration bounded with variation as CHANGE IS INEVITABLE and some change should be done to promote adaptation.